Skip the Salvini unless you want a war in your tank. They do not get that large, but man are they agressive!
Wait until you have the new tank setup and running a few weeks before you buy anymore fish. I would not add anymore cichlids. The ones you have now will all grow before you know it (and being territorial, their claim for tank space will grow accordingly). I would add schooling fish like Silver Dollars, Tinfoil Barbs or Bala Sharks (at least 3 of each, but only choose one species). See if your LFS has Leoporinus or Striped Headstanders, these are interesting fish. You could also add one of the smaller shovelnose cats and/or a pleco. Loaches are hard to treat if they get sick, you really need a quarantine tank (they are sensitive to certain medications). Also, you must get 5 or more, they need to be in groups.
Basically, I would round the tank out into more of a community tank. This way it doesn't turn into a cichlid slugfest all the time. Believe me, this gets frustrating.